This problem is divided into two aspects: first, the head portrait belongs to the right of portrait. Article 100 of the General Principles of the Civil Law stipulates that "citizens have the right to portrait, and their portraits shall not be used for profit without their consent." It can be seen that the behavior that constitutes a violation of citizens' portrait rights usually has two elements: first, without their consent; The second is for the benefit. The common infringement of citizens' portrait rights is mainly the use of other people's portraits in commercial advertisements, commodity decoration, book covers, printed calendars, etc. without their consent. So it's okay to use the avatar part,

Then the signature part. If he claims copyright as an artistic creation, the court should support it, so the signature part is a bit troublesome. Of course, the authentication of the signature remains to be considered.

But I don't think anyone will be held accountable for such a trivial matter, so don't worry. The basic situation is as above, hope to adopt.